/* dirname.c -- return all but the last element in a file name
Copyright (C) 1990, 1998, 2000, 2001, 2003, 2004, 2005, 2006 Free Software
Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
#include<config.h>
#include"dirname.h"
#include<string.h>
#include"xalloc.h"/* Return the length of the prefix of FILE that will be used by
dir_name. If FILE is in the working directory, this returns zero
even though `dir_name (FILE)' will return ".". Works properly even
if there are trailing slashes (by effectively ignoring them). */
size_t
dir_len (charconst *file)
{
size_t prefix_length = FILE_SYSTEM_PREFIX_LEN (file);
size_t length;
/* Advance prefix_length beyond important leading slashes. */
prefix_length += (prefix_length != 0
? (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE
&& ISSLASH (file[prefix_length]))
: (ISSLASH (file[0])
? ((DOUBLE_SLASH_IS_DISTINCT_ROOT
&& ISSLASH (file[1]) && ! ISSLASH (file[2])
? 2 : 1))
: 0));
/* Strip the basename and any redundant slashes before it. */for (length = last_component (file) - file;
prefix_length < length; length--)
if (! ISSLASH (file[length - 1]))
break;
return length;
}
/* In general, we can't use the builtin `dirname' function if available,
since it has different meanings in different environments.
In some environments the builtin `dirname' modifies its argument.
Return the leading directories part of FILE, allocated with xmalloc.
Works properly even if there are trailing slashes (by effectively
ignoring them). Unlike POSIX dirname(), FILE cannot be NULL.
If lstat (FILE) would succeed, then { chdir (dir_name (FILE));
lstat (base_name (FILE)); } will access the same file. Likewise,
if the sequence { chdir (dir_name (FILE));
rename (base_name (FILE), "foo"); } succeeds, you have renamed FILE
to "foo" in the same directory FILE was in. */char *
dir_name (charconst *file)
{
size_t length = dir_len (file);
bool append_dot = (length == 0
|| (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE
&& length == FILE_SYSTEM_PREFIX_LEN (file)
&& file[2] != '\0' && ! ISSLASH (file[2])));
char *dir = xmalloc (length + append_dot + 1);
memcpy (dir, file, length);
if (append_dot)
dir[length++] = '.';
dir[length] = '\0';
return dir;
}